How do you verify the operation of the cheap SIM x terminal?――IIJ introduces the back side of the verification site: IIJmio Meeting 10 (page 1/2)
When using an MVNO SIM, it is important to check whether it can be used on your smartphone. In the past, when MVNO SIMs became unusable due to iOS updates, the support information released by MVNOs attracted a lot of attention. Internet Initiative Japan (IIJ), which develops "IIJmio", is also focusing on checking the operation of SIM-free terminals. The results are posted and updated in the "List of devices whose operation has been confirmed".
At the "IIJmio meeting 10" held in Tokyo on January 23rd, the Consumer Service Department's Service Planning Department discussed how to verify the operation of SIM lock-free terminals and what can be learned from the verification. Mr. Koshi Matsuzaki of the section and Mr. Munenori Ouchi, an engineer at IIJ, introduced the system.
A list of models that have been confirmed to work with "IIJmio" is available on the IIJ website. There are two types of terminal verification that we are doing: "black box test" and "detailed investigation". A black box test is a test method that verifies the functions that can be seen from the outside without considering the internal structure of the terminal, and Mr. Matsuzaki is in charge of this. As a result of the verification, if there is a problem with the behavior of the terminal, Mr. Ouchi's team will investigate in detail.Mr. Koshi Matsuzaki of the Service Planning Division is in charge of the black box test alone. He also talked about the difficulties of updating iOS.I have purchased iPhones, iPads, Nexus series, and terminals handled by the "IIJmio Supply Service", but most of the other terminals rely on various routes. borrowed. Sometimes recruited in-house, sometimes verified at mobile phone corners of partner stores. It seems that the number of manufacturers who provide terminals is increasing because they want them to be listed on the page of terminals that have been confirmed to work.
There are 11 items to be verified, including "LTE compatibility", "SIM size", "tethering", "antenna pictogram", and "IPv6". According to Mr. Matsuzaki, "The content of the verification I am doing is very simple. I just check whether the expected results are returned by testing at the same level as the user sees and confirms." , These verifications are done by Mr. Matsuzaki alone, so it is difficult when the number of terminals is large.
Terminal Verification ItemsFor example, to check LTE compatibility, insert the IIJmio SIM, turn on the power, and check if the LTE pictograph appears. If 3G is displayed, check whether it is accommodated in IIJ's dedicated 3G equipment, or whether it is accommodated in LTE but is 3G by chance due to the area.
When verifying LTE support, we may check our own equipmentTo check whether IPv6 can be used, set the APN of the verification terminal to be able to use IPv6, and the connection log will be an IPv6 IP address. Check if there is For tethering, turn on tethering on the verification terminal, connect another terminal, and check whether you can connect to the Internet from there.
When confirming voice calls, insert the Miofone SIM card and see if you can make and receive calls properly. In the case of Docomo's SIM, it is said that it is convenient because it has a function to call "111" to check the call, but if you hang up the call, it will be called back. Two terminals are used to check "Miofone Dial", which reduces call charges. Make a call with a prefix number and check whether the other party can receive the call and whether the phone number is properly notified.
In the case of a VoLTE compatible terminal, even during a voice call, check if the data communication pictogram does not drop to 3G and the call can be made with LTE. If you want to check the high-quality sound call, prepare another VoLTE compatible terminal and check whether the HD icon is attached during the call.
If the behavior is strange after verification, we will focus on checking it, and if it is unavoidable, the verification team in charge of Mr. Ouchi will investigate in more detail. I make a note of the quirks of each terminal that I found during the verification and the points that I should be careful about, and post them in the remarks when updating the verification information.
Verify 18 iOS devices at 2:00 am and update the information immediately
When a new iPhone is released or when an iOS version is upgraded, the attention of users is very high. Most major iOS updates start at 2:00 am Japan time, so I waited at the office for that. Upgrade all iOS devices for verification. However, since the update starts all over the world at the same time, the update may fail due to congestion. Retrying it over and over again and completing the update is the hardest part. After updating everything, verify the operation, update the web and notify by tweet. All work is expected to be completed by 5am.
18 devices to upgrade iOS. Mr. Matsuzaki will verify this by himselfWhen a new iPhone model is released, of course we will make a reservation. Purchase it on the first day of sale, verify it at a nearby coffee shop, and update the web page immediately. In the case of iPhone and iOS, there is a lot of feedback, so Mr. Matsuzaki says, "We are doing our best to prioritize speed" so that we can announce the results as soon as possible.
Various problems were discovered in these verifications. With iOS 7, iPhone 4 and iPad 2 could not communicate with data communication SIM, and with iOS 8.x, data SIM could not communicate with iPad 4 and iPad mini with LTE communication. At this time, Mr. Ouchi's verification team conducted more detailed checks, and the results were announced at past IIJmio meetings. Even recently, iOS 9 can no longer use the old version of the configuration profile, but IIJ has provided a new configuration profile as soon as possible.
Slides are posted in the IIJmio meeting ARCHIVE about verifying and coping with various problemsIn Android 4.3 (Jelly Beans), IIJmio's APN was added to the list for the first time, and SIM Mr. Matsuzaki said that he was moved by the fact that he was able to connect automatically just by plugging in and turning on the power. However, in Android 5.0 (Lolipop), this became an adder, and there were times when the data communication connection became unstable during APN search. In this case, the Ouchi team also verified it and proposed a countermeasure to stabilize it by deleting the APN settings other than the ones you use.
In the past, IIJ's verifications have clarified the strange behavior of iPhones and Android devices. While prefaced by the fact that the operation is not completely guaranteed, Mr. Matsuzaki said, "Since we are actually verifying in detail, please feel free to pick up the terminals on our list."
You may also see a rare SIM card slot during verification. Two SIM slots are commonplace for SIM lock-free terminals. Some terminals are equipped with a combined nanoSIM/microSD slot, or a slot combining a combined nanoSIM/microSD slot and a microSIM slotFor the problem, use various verification tools to investigate in detail /h3>
If Mr. Matsuzaki finds a problem with the terminal, Mr. Ouchi's team will conduct a detailed investigation to investigate the cause and workarounds.
If a problem is found in the black box test, use various tools to conduct a more detailed investigationMr. Ouchi of IIJIn this investigation, the terminal Analysis of internal files and setting values, source code analysis, data communication analysis with the outside, and mobile control signal analysis are performed.
Investigate log files, setting files, and setting values in the terminal when analyzing internal files and setting values. The meaning of these settings is rarely published, so you can search the web or guess. Source code analysis directly confirms the implementation related to terminal communication, but this can only be done on Android terminals whose source code is open to the public. Check the source code published by the Android Open Source Project or research information you can find on the web about chip vendor implementations.
When analyzing data communication with the outside, cancel SSL and check the contents. For example, it is said that the information that the iOS terminal communicates with Apple's server can also be confirmed using the tool.
Mobile control signal analysis is a survey performed when mobile data communication is not stable. Examine the mobile control information between the terminal and the base station and analyze its behavior. In fact, the number of terminals that can be used is limited, and it is said that only if the terminal uses a Qualcomm chip and has a debug mode that can extract control information.
Method for analyzing internal files and settingsMethod for analyzing source codeMethod for analyzing data communicationMethod for analyzing mobile control signalsThe verification tools are mostly free software with a few exceptions. In addition to the Android SDK, we also use a tool called "plutil.pl" that can convert the iOS carrier setting file to a text base, and a tool that allows you to see the internal information of the device that cannot be seen without privileges. Also, check the meaning of the information by searching on the Web.
For mobile control signal analysis, Meritech's commercial tool "Sigma-ML/LA/PA" is used to visualize the acquired data.
By conducting such a detailed investigation, it was found that GPS may not work with MVNO SIMs and data communication may become unstable. Information that GPS does not work at MVNOs was circulated on SNS, etc., so Mr. Ouchi investigated and summarized it, and introduced the verification results at IIJmio meeting 5. IIJmio meetings 7 and 8 explained the verification results in detail about the data communication instability problem.
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